libstdc++-v3/include/ext/pod_char_traits.h

   1 // POD character, std::char_traits specialization -*- C++ -*-
   2
   3 // Copyright (C) 2002, 2003, 2004, 2005, 2007 Free Software Foundation, Inc.
   4 //
   5 // This file is part of the GNU ISO C++ Library.  This library is free
   6 // software; you can redistribute it and/or modify it under the
   7 // terms of the GNU General Public License as published by the
   8 // Free Software Foundation; either version 2, or (at your option)
   9 // any later version.
  10
  11 // This library is distributed in the hope that it will be useful,
  12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 // GNU General Public License for more details.
  15
  16 // You should have received a copy of the GNU General Public License along
  17 // with this library; see the file COPYING.  If not, write to the Free
  18 // Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
  19 // USA.
  20
  21 // As a special exception, you may use this file as part of a free software
  22 // library without restriction.  Specifically, if other files instantiate
  23 // templates or use macros or inline functions from this file, or you compile
  24 // this file and link it with other files to produce an executable, this
  25 // file does not by itself cause the resulting executable to be covered by
  26 // the GNU General Public License.  This exception does not however
  27 // invalidate any other reasons why the executable file might be covered by
  28 // the GNU General Public License.
  29
  30 /** @file ext/pod_char_traits.h
  31  *  This file is a GNU extension to the Standard C++ Library.
  32  */
  33
  34 // Gabriel Dos Reis <gdr@integrable-solutions.net>
  35 // Benjamin Kosnik <bkoz@redhat.com>
  36
  37 #ifndef _POD_CHAR_TRAITS_H
  38 #define _POD_CHAR_TRAITS_H 1
  39
  40 #include <string>
  41
  42 _GLIBCXX_BEGIN_NAMESPACE(__gnu_cxx)
  43
  44   // POD character abstraction.
  45   // NB: The char_type parameter is a subset of int_type, as to allow
  46   // int_type to properly hold the full range of char_type values as
  47   // well as EOF.
  48   /// @brief A POD class that serves as a character abstraction class.
  49   template<typename V, typename I, typename S = std::mbstate_t>
  50     struct character
  51     {
  52       typedef V                         value_type;
  53       typedef I                         int_type;
  54       typedef S                         state_type;
  55       typedef character<V, I, S>        char_type;
  56
  57       value_type        value;
  58
  59       template<typename V2>
  60         static char_type
  61         from(const V2& v)
  62         {
  63           char_type ret = { static_cast<value_type>(v) };
  64           return ret;
  65         }
  66
  67       template<typename V2>
  68         static V2
  69         to(const char_type& c)
  70         {
  71           V2 ret = { static_cast<V2>(c.value) };
  72           return ret;
  73         }
  74
  75     };
  76
  77   template<typename V, typename I, typename S>
  78     inline bool
  79     operator==(const character<V, I, S>& lhs, const character<V, I, S>& rhs)
  80     { return lhs.value == rhs.value; }
  81
  82   template<typename V, typename I, typename S>
  83     inline bool
  84     operator<(const character<V, I, S>& lhs, const character<V, I, S>& rhs)
  85     { return lhs.value < rhs.value; }
  86
  87 _GLIBCXX_END_NAMESPACE
  88
  89 _GLIBCXX_BEGIN_NAMESPACE(std)
  90
  91   /// char_traits<__gnu_cxx::character> specialization.
  92   template<typename V, typename I, typename S>
  93     struct char_traits<__gnu_cxx::character<V, I, S> >
  94     {
  95       typedef __gnu_cxx::character<V, I, S>     char_type;
  96       typedef typename char_type::int_type      int_type;
  97       typedef typename char_type::state_type    state_type;
  98       typedef fpos<state_type>                  pos_type;
  99       typedef streamoff                         off_type;
 100
 101       static void
 102       assign(char_type& __c1, const char_type& __c2)
 103       { __c1 = __c2; }
 104
 105       static bool
 106       eq(const char_type& __c1, const char_type& __c2)
 107       { return __c1 == __c2; }
 108
 109       static bool
 110       lt(const char_type& __c1, const char_type& __c2)
 111       { return __c1 < __c2; }
 112
 113       static int
 114       compare(const char_type* __s1, const char_type* __s2, size_t __n)
 115       {
 116         for (size_t __i = 0; __i < __n; ++__i)
 117           if (!eq(__s1[__i], __s2[__i]))
 118             return lt(__s1[__i], __s2[__i]) ? -1 : 1;
 119         return 0;
 120       }
 121
 122       static size_t
 123       length(const char_type* __s)
 124       {
 125         const char_type* __p = __s;
 126         while (__p->value)
 127           ++__p;
 128         return (__p - __s);
 129       }
 130
 131       static const char_type*
 132       find(const char_type* __s, size_t __n, const char_type& __a)
 133       {
 134         for (const char_type* __p = __s; size_t(__p - __s) < __n; ++__p)
 135           if (*__p == __a)
 136             return __p;
 137         return 0;
 138       }
 139
 140       static char_type*
 141       move(char_type* __s1, const char_type* __s2, size_t __n)
 142       {
 143         return static_cast<char_type*>
 144           (__builtin_memmove(__s1, __s2, __n * sizeof(char_type)));
 145       }
 146
 147       static char_type*
 148       copy(char_type* __s1, const char_type* __s2, size_t __n)
 149       {
 150         std::copy(__s2, __s2 + __n, __s1);
 151         return __s1;
 152       }
 153
 154       static char_type*
 155       assign(char_type* __s, size_t __n, char_type __a)
 156       {
 157         std::fill_n(__s, __n, __a);
 158         return __s;
 159       }
 160
 161       static char_type
 162       to_char_type(const int_type& __i)
 163       { return char_type::template from(__i); }
 164
 165       static int_type
 166       to_int_type(const char_type& __c)
 167       { return char_type::template to<int_type>(__c); }
 168
 169       static bool
 170       eq_int_type(const int_type& __c1, const int_type& __c2)
 171       { return __c1 == __c2; }
 172
 173       static int_type
 174       eof()
 175       {
 176         int_type __r = { -1 };
 177         return __r;
 178       }
 179
 180       static int_type
 181       not_eof(const int_type& __c)
 182       { return eq_int_type(__c, eof()) ? int_type() : __c; }
 183     };
 184
 185 _GLIBCXX_END_NAMESPACE
 186
 187 #endif